Effects of Thin Film Morphology of Polymer Hole Transfer Material on Photovoltaic Performance of Perovskite Solar Cells

In the present study, the effects of chain length variation of Poly(3-hexyl) thiophene polymer, which is one of the appropriate alternatives of Spiro-O-MeTAD used as a hole transfer layer (HTL) in perovskite-based solar cells (PSC), on thin-film morphology and device performance were investigated. Furthermore, nanowires of long (UZ) and short-chain (KZ) P3HT were obtained in the solution phase and then comparative photovoltaic performance analyses were carried out by fabricating PSC devices. As a result, it was determined that the morphological changes resulting from the polymer chain length directly affect the charge transfer between the active layer and HTL. KZ-P3HT presented better performance than both standard P3HT (5.99) and UZ-P3HT (2.68) polymers with a power conversion efficiency (PCE) of 7.74%. It was demonstrated that the main reason for this is that the fringed structure, detected by AFM images, increases the contact ratio at the perovskite/HTM interface. In addition, thanks to the morphological improvements in nano-wire studies, it was observed that the photovoltaic performance of the PSC device containing UZ-P3HT increased by 5.51%. Contrary to UZ-P3HT, it was determined that after the conversion of KZ-P3HT to the nanowire, the fringed structure on the surface disappeared and therefore the efficiency decreased to 5.81%.

___

  • “Best Research-Cell Efficiency Chart | Photovoltaic Research | NREL.” https://www.nrel.gov/pv/cell-efficiency.html (accessed Dec.. 3, 2021).
  • M. Saliba et al., 2016, “Cesium-containing triple cation perovskite solar cells: Improved stability, reproducibility and high efficiency,” Energy and Environmental Science, 9(6), 1989–1997.
  • M. Liu, M. B. Johnston, and H. J. Snaith, 2013, “Efficient planar heterojunction perovskite solar cells by vapour deposition,” Nature, 501(7467): 395–398.
  • O. Almora et al., 2021, “Device Performance of Emerging Photovoltaic Materials (Version 1),” Advanced Energy Materials, 11(11).
  • S. S. Ashrafi et al., 2020, “Characterization and Fabrication of Pb-Based Perovskites Solar Cells under Atmospheric Condition and Stability Enhancement,” Advances in Materials Physics and Chemistry, 10(11): 282–296.
  • Q. Chen et al., 2014, “Planar Heterojunction Perovskite Solar Cells via Vapor-Assisted Solution Process,”, Journal of the American Chemical Society, 136(2): 3–6.
  • G. E. Eperon, V. M. Burlakov, P. Docampo, A. Goriely, and H. J. Snaith, 2014, “Morphological Control for High Performance , Solution- Processed Planar Heterojunction Perovskite Solar Cells,”, Advanced Functional Materials, 24 (1): 151–157.
  • S. Rutile et al., 2013, “High Efficiency Solid-State Sensitized Solar Cell-Based on Submicrometer Rutile TiO 2 Nanorod and CH 3 NH 3 PbI 3 Perovskite Sensitizer”, Nano Letters, 13(6): 2412-2417.
  • K. Wojciechowski, M. Saliba, T. Leijtens, A. Abate, and H. J. Snaith, 2014, “Environmental Science Sub-150 C processed meso-superstructured perovskite solar cells with enhanced efficiency”, Energy and Environmental Science, 7(3), 1142–1147.
  • Q. An, P. Fassl, Y. J. Hofstetter, D. Becker-koch, and A. Bausch, 2017, “Nano Energy High performance planar perovskite solar cells by ZnO electron transport layer engineering”, Nano Energy, 39(4): 400–408.
  • T. Matsui, W. Tress, M. Saliba, A. Abate, M. Gra, and A. Hagfeldt, 2016, “Environmental Science cells by solution-processed tin oxide”, Energy & Environmental Science, 9: 3128–3134.
  • Y. Wu et al., 2016, “Perovskite solar cells with 18.21% efficiency and area over 1 cm2 fabricated by heterojunction engineering”, Nature Energy, 1(11):1–7.
  • P. Yadav, D. Prochowicz, M. Saliba, P. P. Boix, S. M. Zakeeruddin, and M. Grätzel, 2017, “Interfacial kinetics of efficient perovskite solar cells,” Crystals, 7(8):1–9.
  • L. Miao, Z. Song, D. Zhu, L. Li, L. Gan, and M. Liu, 2020, “Recent advances in carbon-based supercapacitors,” Materials Advances, 1(5):945–966.
  • T. Leijtens, K. Bush, R. Cheacharoen, R. Beal, A. Bowring, and M. D. McGehee, 2017, “Towards enabling stable lead halide perovskite solar cells,” J. Mater. Chem. A, 5(23), 11483–11500.
  • M. Kim et al., 2021, “Moisture resistance in perovskite solar cells attributed to a water-splitting layer,” Communications Materials 2021 2:1, 2(1), 1–12.
  • G. Ren et al., 2021, “Strategies of modifying spiro-OMeTAD materials for perovskite solar cells: a review,” Journal of Materials Chemistry A, 9(8): 4589–4625.
  • J. Y. Seo et al., 2021, “Dopant Engineering for Spiro-OMeTAD Hole-Transporting Materials towards Efficient Perovskite Solar Cells,” Advanced Functional Materials, 31(45): 2102124.
  • X. Sun, X. Yu, and Z. Li, 2020, “Recent advances of dopant-free polymer hole-transporting materials for perovskite solar cells,” ACS Applied Energy Materials, 3(11): 10282–10302.
  • N. Yaghoobi Nia et al., 2021, “Impact of P3HT Regioregularity and Molecular Weight on the Efficiency and Stability of Perovskite Solar Cells,” ACS Sustainable Chemistry and Engineering, 9(14): 5061–5073.
  • Y. Zhang, M. Elawad, Z. Yu, X. Jiang, J. Lai, and L. Sun, 2016, “Enhanced performance of perovskite solar cells with P3HT hole-transporting materials via molecular p-type doping,” RSC Advances, 6(110): 108888–108895.
  • E. H. Jung et al., 2019, “Efficient, stable and scalable perovskite solar cells using poly(3-hexylthiophene),” Nature 2019 567:7749, 567(7749): 511–515.
  • N. Y. Nia, F. Matteocci, L. Cina, and A. Di Carlo, 2017, “High-Efficiency Perovskite Solar Cell Based on Poly(3-Hexylthiophene): Influence of Molecular Weight and Mesoscopic Scaffold Layer,” ChemSusChem, 10(19): 3854–3860.
  • D. Kiymaz, A. Kiymaz, and C. Zafer, 2020, “Performance improvement of P3HT nanowire-based organic solar cells by interfacial morphology engineering,” Nanotechnology: 32(10), 105401.
  • N. Y. Nia, F. Matteocci, L. Cina, and A. Di, 2017, “High-Efficiency Perovskite Solar Cell Based on Poly ( 3-Hexylthiophene ): Influence of Molecular Weight and Mesoscopic Scaffold Layer,” Aldo Di Carlo, 10 (19) : 3854–3860.
  • M. Sapolsky and D. Boucher, 2018, “Poly ( 3-Hexylthiophene ) Aggregation at Solvent – Solvent Interfaces,” Journal of Polymer Science, Part B: Polymer Physics, 56 (13): 999–1011.
  • Y. Wang et al., 2017, “Stitching triple cation perovskite by a mixed anti-solvent process for high performance perovskite solar cells,” Nano Energy, 39(July): 616–625.
  • J. W. Lee, S. H. Bae, N. De Marco, Y. T. Hsieh, Z. Dai, and Y. Yang, 2018, “The role of grain boundaries in perovskite solar cells,” Materials Today Energy, 7: 149–160.
  • L. Tian et al., 2020, “Effects of Annealing Time on Triple Cation Perovskite Films and Their Solar Cells,” ACS Applied Materials and Interfaces, 12(26): 29344–29356.